Process of photo-engraving



arch 25 J. DE GRAVE PROCESS OF PHOTO ENGRAVING Filed OCT.. 13 1922 2 SheetB-Sheet-1 Mwah 25 ga ,4871,727

M. J. DE: GRAVE PROCESS OF PHOTO ENGRAVING Filed OC'C. 13 1922 2 Sheets-Sheet 2 Patented Mar. 25, 19524.

@MF FFS MICHAEL J. DE GRAVE, OF CHICAGO, ILLINOIS.

PROCESS OF PHOTO-ENGRAVING.

Application led October 13, 1922. Serial No. 594,257.

To all whom t may omwem:

Be it known that I, MICHAEL J. DE GRAVE, a citizen of the United States, and a resident of the city of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Processes of Photo-Engraving, of which the following is a specification.

My invention relates to improvements in process of photo-engraving, and has for its object the provision of an improved process or method of this character, by means of which light and shade, pattern and other effects may be artistically produced by means of such plates.

Other objects will appear hereinafter.

The invention consists in the process and method of procedure hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings forming a part of this specification, and-in which,

Fig. 1 is a view of a out such as may be made from a plate prepared by the process;

Fig. 2, a diagrammatic view of a portion of such cut enlarged to illustrate substantially the result attained by the use of the process;

Fig. 3, a view similar to Fig. 1 illustrating the same cut substantially as it would appear without the use of the process; and

Fig. 4, a view similar to Fig. 2 as the corresponding portion of the cut would appear without the use of a recess.

The preferred metliod of procedure consists in first preparing a photo-engraving or half tone plate in the usual way for etching. As will be readily understood by those skilled in this art, such a plate is prepared by first making a photographic negative of the object to be produced. A zinc or copper plate coated with a sensitized coating is then covered, rst with a screen of mesh material and then the protograp-hic negative is laid over this screen and the whole exposed to light. The light passing through the negative and meshes of the screen to the sensitized coating of the plate renders the protecting coating soluble Where the light strikes, the other portions of the coating remaining insoluble.

n the ordinary process of photo-engraving the half tone plate thus prepared is then etched in acid to produce the plate for printing.

Instead of proceeding at once with this etching I subject the plate to a preliminary treatment for the removal of certain portions of the insoluble portions of the coating. This is preferably done by means of an engravers tool. To this end I scrape from the plate certain portions of the insoluble protecting coating, remov-in therewith part of the underlying plate. gIhen the plate is etched in the usual Way, the action of the etching acid serving to blend and tone down the effects produced by the removal of the protecting coating to such an extent as to produce a soft blended effect inthe cut or print, the etching process also removing any burrs or rough edges resulting from the use of the tool on the plate.

In order to render the invention clear, I have endeavored to illustrate in Fig. 4 a portion of a print or cut which would result from a'n ordinary photo-engraving or half tone plate, and in Fig. 2 the corresponding portion of the cut or print which would result after the use of my process. In Fig. 2 the blank portions marked with the numeral 5 represents the eect produced by the removal of the protecting coating at the corresponding points in the plate, such removal resulting in blank portions in the print, and I have endeavored to illustrate in Fig. 1, and more particularly in the front collar portion thereof the visual effect thus produced. In the instance illustrated I have illustrated the retouching of the plate to bring out or emphasize the pattern of the cloth of Which the shirt illustrated is composed. To this end the portions corresponding with the spaces 5 have all been removed from certain diagonal lines of the plate, leaving the intermediate lines or portions 6 intact or substantially so. In the print as will be observed by comparison between Figs. 1 and 3, this produces diagonal line eifects to indicate a corresponding pattern.

in the cloth of which the shirt is composed. Likewise, it will be observed, that in this manner certain effects of light and shade may be produced which cause portions of the cut or print to stand out in relief, thus materially increasing the artistic appearance of the print as indicated.

While I have illustrated and described the preferred method of procedure for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the Oil precise process or method set forth, but desire to avail myself of such variations and modifications as come Within the scope of the appended claims.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

l. The method of preparing photo-engrava ings which consists in covering a metal plate with a sensitized coating and exposing the same to the action of light operatingthrough a photographic negative and a screen; then removing by hand certain of the screen marks from said coating; and then etching said plate, substantially as described.

2. The method of preparing photo-engravings which consists in covering a metal plate with a sensitized coating and exposing the same to the action of light passing through a photographic negative and a screen; then treating said plate to prevent'printing of selected portions of the screen marks; and then etchin said plate, substantially as described.

3. e method of preparing photo-engravings which consist in coating la metal plate with a sensitized coating and exposing the same to the action of light o rating through a photograph negative an a screen; then removing by hand certain of the screen marks from said coating together With underlying metal; and then etching said plate, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MICHAEL J. DE GRAVE.

Witnesses:

JOSHUA R. II.PoTTs, FREDA C. APPLETON. 

